Today supermarkets and shops sell products such as carbonated drinks in increasingly large volumes. The containers, which are usually plastic bottles, generally hold volumes of up to around 3 liters of liquid although there is no reason why larger containers cannot be used.
Perhaps the main advantage to the customer and producer with respect to buying and selling this type of product in bulk, say 3 liter bottles, is the reduction in overall production costs and thereby sale prices of the product in comparison to the same product in smaller containers. Bulk containers are easier to handle and cheaper to make than the large number of small bottles or cartons used to hold a similar volume of product.
A serious problem, however, with buying carbonated drinks in large containers is that once the container has been opened and a quantity of the liquid removed, the quality i.e. the "fizzyness" of the product remaining in the container deteriorates over a relatively short period of time. Eventually, the quality deteriorates to the point where there is only a negligible amount of carbon dioxide remaining in the liquid, the majority of the carbon dioxide being in the gaseous atmosphere of the bottle. This is because of the change in gas/liquid pressure equilibrium within the container resulting from the volume of liquid which had been poured from the container.
Therefore despite saving a small amount of money through buying the liquid in a bulk container, often unless all the liquid is consumed in a short period of time, say 6-12 hours, the liquid remaining in the container becomes undrinkable and is subsequently disposed of. Hence, by throwing away the residual liquid all the money saved by buying in bulk is lost because the liquid was not used quickly enough.